v3.24.2.u1
Stock-Based Compensation - Additional Information (Detail) - USD ($)
$ / shares in Units, $ in Millions
1 Months Ended 3 Months Ended 6 Months Ended
May 30, 2023
Jan. 31, 2024
Mar. 31, 2024
Jun. 30, 2024
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Restricted Stock Units, Granted       848,476
Fair value of RSUs/restricted stock granted to employees       $ 680
Maximum [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Award vesting period, years       5 years
Minimum [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Award vesting period, years       2 years
Restricted Stock Units (RSUs) [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Restricted Stock Units, Granted   347,000    
Award vesting period, years   3 years    
Awards to employees cliff vesting   344,000    
RSUs to employees that cliff vest, percentage   100.00%    
RSUs to employees that cliff vest, date   Jan. 31, 2027    
Intrinsic value of outstanding RSUs       $ 1,500
Stock price       $ 787.32
Unrecognized stock-based compensation expense       $ 766
Remaining weighted-average period       1 year 8 months 12 days
Restricted Stock Units (RSUs) [Member] | GIP Transaction [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Restricted Stock Units, Granted     106,000  
Performance-Based RSUs [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Restricted Stock Units, Granted       165,631
Award vesting period, years   3 years    
Awards to employees cliff vesting   165,631    
RSUs to employees that cliff vest, percentage   100.00%    
RSUs to employees that cliff vest, date   Jan. 31, 2027    
Share based compensation vesting option exercised period       up to nine years
Intrinsic value of outstanding RSUs       $ 365
Stock price       $ 787.32
Unrecognized stock-based compensation expense       $ 168
Remaining weighted-average period       1 year 8 months 12 days
Fair value of RSUs/restricted stock granted to employees       $ 101
Performance Based Stock Options [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of shares awarded to purchase 814,482      
Share based compensation vesting option exercised period       up to nine years
Award vesting percentage of BlackRock's grant-date stock price 130.00%     125.00%
Award vesting period of BlackRock's grant-date stock price       5 years
Award performance measurement period       4 years
Aggregate intrinsic value of options exercised       $ 92
Performance Based Stock Options [Member] | Share-based Payment Arrangement, Tranche One [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
RSUs to employees that cliff vest, percentage 25.00%      
RSUs to employees that cliff vest, vesting date May 30, 2027      
Service year of awards       2022
Performance Based Stock Options [Member] | Share-based Payment Arrangement, Tranche Two [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
RSUs to employees that cliff vest, percentage 25.00%      
RSUs to employees that cliff vest, vesting date May 30, 2028      
Service year of awards       2023
Performance Based Stock Options [Member] | Share-based Payment Arrangement, Tranche Three [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
RSUs to employees that cliff vest, percentage 50.00%      
RSUs to employees that cliff vest, vesting date May 30, 2029      
Service year of awards       2024
Time-based stock options        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of shares awarded to purchase 326,391      
Share based compensation vesting option exercised period up to nine years      
Remaining weighted-average period       2 years 10 months 24 days
Unrecognized stock-based compensation expense       $ 131
Time-based stock options | Share-based Payment Arrangement, Tranche One [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
RSUs to employees that cliff vest, percentage 25.00%      
RSUs to employees that cliff vest, vesting date May 30, 2027      
Time-based stock options | Share-based Payment Arrangement, Tranche Two [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
RSUs to employees that cliff vest, percentage 25.00%      
RSUs to employees that cliff vest, vesting date May 30, 2028      
Time-based stock options | Share-based Payment Arrangement, Tranche Three [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
RSUs to employees that cliff vest, percentage 50.00%      
RSUs to employees that cliff vest, vesting date May 30, 2029